The was a multi-stage bundle released for 1,000 Credits that unlocked content in three main waves (Kickoff, Thanksgiving, and Super Bowl LVI). The "part 4" in your query likely refers to the final content drop or a specific archive of these assets. Included Items
32 animated Octane Decals , 32 Team Player Banners, and 32 Team Antennas. Rocket.League.NFL.Fan.Pass.part4.rar
The pass provided a comprehensive set of items for all 32 NFL teams: The was a multi-stage bundle released for 1,000
32 animated Dominus Decals and the Pigskin Paint Finish . 32 Team Player Banners